Multiple Sclerosis
Jill C. Cash and Kimberly D. Waltrip
Definition
A.Multiple sclerosis (MS) is an autoimmune degenerative disease that damages neuronal axons and breaks down myelin sheaths. The process of inflammatory demyelination varies in progression with recurrent relapse and remission of symptoms over time. The most common symptoms include visual disturbances, spastic paraparesis, and bladder dysfunction. The course of MS is typically intermittent with periodic exacerbations occurring in various areas of the central nervous system (CNS).
B.MS can also present more acutely in severity, progression, and variety of symptoms. Early diagnosis is difficult, but crucial for effective treatment. An MS attack or exacerbation lasts at least 24 hours, occurring without fever or any infectious process. Complete recovery after the first exacerbation is common, presenting as a clinically isolated syndrome, but typically converting to MS within 5 years. Subsequent progression of the disease with recurrent exacerbations diminishes physical function over time.
C.The loss of myelin leads to neurological deficits in vision, speech, gait, writing, and memory, and can affect the swallow or cough reflex. Individuals typically present to the ED upon relapse with 80% experiencing exacerbations of previous deficits. Clinical diagnosis is supported when at least one reported exacerbation correlates with MS-related findings obtained during the neurological exam, with MRI, or with visual evoked potential (VEP) studies if visual disturbances are reported.
MS is classified as relapsing-remitting (RR) or progressive, and further described as active versus not active, with or without progression. Progressive MS is further differentiated with the following two subtypes:
A.RR affects approximately 85% of MS patients; exacerbations of symptoms and periodic remission occur.
B.Primary progressive (PP) is a less common form of MS, accounting for around 10% of MS cases; primary progressive multiple sclerosis (PPMS) progresses slowly without periods of relapse or remission.
C.Secondary progressive (SP): It is not unusual for patients with relapsing-remitting multiple sclerosis (RRMS) to progress to secondary progressive multiple sclerosis (SPMS) over time. Progression of the disease process continues with or without periods of remission. Symptoms do not necessarily decrease or stabilize in terms of severity.
Incidence
A.Currently, the Multiple Sclerosis Foundation estimates 400,000 individuals in the United States have been diagnosed with MS and that there are a total of 2.5 million cases worldwide (as reported by other international organizations). It is one of the leading causes of disability in young adults. These statistics are challenged when U.S. physicians are not required to report new cases of MS and when diagnosis is questionably accurate. The signs and symptoms of MS may not be recognized or reported initially, nor when persisting over time; they may also be defined as other disease processes.
B.MS is typically diagnosed in adults between 20 and 50 years of age. Between 4% and 9% of individuals with MS experience onset of symptoms after age 50. However, lateonset multiple sclerosis (LOMS)
has been diagnosed in adults older than age 55. The occurrence of MS is even less prevalent in those older than age 60. This may be associated with improved health-care and longevity.
Pathogenesis
A.The cause of MS is unknown. A suspected combination of genetic predisposition and a trigger (chronic viral infections, environmental factors, metabolic issues) may create an autoimmune disorder that facilitates the degenerative disease process.
B.Autoimmune attacks on the myelin sheaths of neurons initiate an inflammatory response, followed by eventual plaque formation and scarring, the hallmark characteristic of the disease.
C.A loss of saltatory conduction is noted. Axonal death occurs during this acute inflammatory response, explaining any permanent disability. The associated inflammation and edema around a MS lesion, along with myelin and axonal loss, contribute to the associated neurologic deficit. A limited amount of remyelination and the eventual resolution of inflammation will allow a certain degree of recovery with remission. With each exacerbation, there is a lesser degree of recovery and subsequent decrease in function.
Predisposing Factors
A.Family history of MS.
B.Female gender (two times more likely than men to develop MS).
C.Age 20 to 50 (onset can vary from age 10 to 70).
D.Caucasian race (Northern European ancestry).
E.Environment (living in temperate zones, e.g., Canada, northern areas of the United States, Europe). This is associated with prevalence, but no direct link has been established at this time; it is suspected that this distance from the equator causes a vitamin D deficiency secondary to a lack of direct sunlight, contributing to the development of MS.
F.Previous chronic viral infection may increase susceptibility.
G.Smoking.
Common Complaints
A.Sensory loss (paresthesia) is often reported early in the course of the disease.
B.Visual disturbances: Diplopia upon lateral gaze (occurs in 33% of individuals with MS), blurred vision, loss of vision, and ocular pain.
C.Urinary incontinence, frequency, hesitancy, or urgency (>90% of individuals with MS report bladder dysfunction).
D.Fatigue (in up to 90% of individuals with MS).
E.Weakness in one or more extremities.
F.Gait imbalance (within 15 years of onset, 50% will require assistance during ambulation).
Other Signs and Symptoms
A.Babinski response.
B.Spasticity (usually in lower extremities).
C.Depression (nearly 50% of cases; also reported effects on memory, attention, and concentration).
D.Hyperreflexia.
E.Loss of proprioception.
F.Impotence (males).
G.Impaired cognition: Subjective difficulties with attention, concentration, short-term memory, planning, and judgment; dementia reported in 3% of individuals with latestage MS.
H.Dysarthria.
I.Reduced libido (in both males and females).
J.Constipation.
K.Pain.
L.Trigeminal neuralgia (TN; rare).
M.Dysphagia (may also have recurrent respiratory infections secondary to aspiration).
N.Vertigo (in 30%–50% of individuals with MS).
Subjective Data
A.Establish location and onset of symptoms. Is this the first time the patient has experienced the symptom in question? Was the onset acute or insidious?
B.Ask the patient to describe the quality and severity of the symptom and how it has evolved over time, including duration. Is there a relapse-remitting pattern? Is the symptom progressing in
severity?
C.Ask the patient if any associated factors aggravate or alleviate the symptom. Does hot weather (as well as hot tubs, saunas, and overexertion) aggravate the condition? Does rest help? Did the symptom resolve spontaneously?
D.Establish if any viral or bacterial infections occurred prior to onset of symptoms.
E.Evaluate visual complaints, including the presence of scotoma, decreased color perception, diplopia, decreased acuity, or painful extraocular eye movements. Is visual deterioration induced by exercise, a hot meal, or a hot bath (the Uhthoff’s phenomenon)?
Physical Examination
A.Check blood pressure (BP), pulse, and respirations.
B.Inspect:
1.Perform a complete eye exam (use Snellen eye chart; test cranial nerve [CN] II, III, IV, and VI):
a.50% of individuals with MS present with retrobulbar involvement but have no abnormal findings upon fundoscopic exam.
b.Anterior involvement causes papillitis; look for the presence of macular star.
c.Assess pupillary response bilaterally; look for pendular nystagmus or sinusoidal involuntary oscillations in one or both eyes, and/or loss of smooth eye pursuit.
2.Perform a neurological and a musculoskeletal exam:
a.Sensory: Test for perception of sharp versus dull stimulus, heat versus cold stimulus, ability to localize pain, proprioception, and vibratory sense, utilizing the tuning fork to evaluate.
b.Motor strength (test all extremities); also observe for increased tone (spasticity), clonus, and tremors.
c.Romberg test and heel-to-toe tandem gait testing (evaluate for ataxia, cerebellar involvement).
d.Finger-to-nose testing and heel-to-shin testing (rule out dystaxia).
e.Check deep tendon reflexes (DTRs) to assess for hyperreflexia; Babinski response may also be present in individuals with MS.
f.Assess mental status (orientation to person, place, time, and situation); test short-term memory and the ability to plan—impaired planning is a cognitive deficit associated with MS.
g.Assess for pain: Include location, descriptive characteristics, onset, duration, timing and setting, aggravating factors, alleviating factors, and any other associated information.
h.Assess for depression, especially with progression of symptoms.
Diagnostic Tests
A.There is no specific confirmatory test for MS.
B.MRI is the test of choice supporting clinical diagnosis of MS. An MRI of the brain will reveal the associated plaques when present, but it cannot determine whether these particular lesions are specific to MS (similar radiographic findings are noted with other diseases):
1.Transverse myelitis lesions identified with MRI may convert to MS over time.
C.Cerebrospinal fluid (CSF) analysis: Characteristics of MS include the presence of oligoclonal bands (85%–90% of MS cases), increased immunoglobulin G (IgG; >12%), and increased white blood cells (WBCs; >5%).
D.Evoked response (ER) or evoked potential (EP): Several different tests evaluate brain function and nerve conduction velocity (NCV):
1.Brain auditory evoked response (BAER) detecting subtle changes in brainstem function with hearing.
2.Visual interpretation and perception (VEP), evoked visual response to flash and pattern reversal (VER).
3.Somatosensory evoked potential (SSEP) studies evaluate nerve conduction from the extremities via the spinal cord to the brain.
E.Complete blood count (CBC) with differential.
F.Serum glucose to rule out hypoglycemia and chronic hyperglycemia as potential causes of neurologic findings.
Differential Diagnoses
A.MS.
B.CNS lymphoma.
C.CNS infection.
D.Acute disseminated encephalomyelitis (ADEM).
E.Tumor: Brainstem, cerebellar, or spinal cord.
F.Amyotrophic lateral sclerosis (ALS).
G.Systemic lupus erythematosus (SLE).
H.Syringomyelia.
I.Progressive multifocal leukoencephalopathy (PML).
J.Sarcoidosis.
K.Sjogren’s syndrome.
L.Acute transverse myelitis.
M.Myasthenia gravis (MG).
N.Guillain–Barré syndrome (GBS).
O.Cerebrovascular accident (CVA).
P.Diabetes mellitus (DM).
Q.Spinal cord compression (stenosis, ruptured disk).
R.Behcet’s disease.
S.Neuromyelitis optica (NMO).
Plan
A.Patient teaching:
1.Educate on heat sensitivity and how it can aggravate symptoms: Avoid hot tubs, saunas, prolonged exposure in hot/humid weather; choose appropriate clothing for the season. Around 60% of individuals with MS experience heat sensitivity, facilitating a pseudoexacerbation where MS symptoms may worsen, but do not necessarily indicate additional axon or myelin degeneration.
2.For visual disturbances, offer advice on resting the eyes at various times during the day; for diplopia, an eye patch can be used temporarily.
3.Stress the importance of exercise and its effect on MS-related fatigue and spasticity; overactivity/overexertion is another issue to address at this time. Rest periods are needed during exacerbations.
4.Provide education on Kegel’s exercises and timed voiding to improve bladder function; also advise to avoid alcohol and caffeinated beverages.
5.Promote increased water intake, dietary fiber intake, and physical activity for increased bowel motility.
6.Educate regarding the signs and symptoms of infection, especially urinary tract infections (UTIs), and how infection can trigger an exacerbation.
7.Instruct safe performance of self-intermittent catheterization (SIC) for urinary retention and emphasize the importance of sterile technique.
8.Discuss the purpose and availability of local MS support groups.
9.Discuss counseling services for development of adaptive coping techniques, improved family dynamics and relationships with significant others, adjustment to physical disability, and any anticipatory grief issues.
10.Educate on all medications, including side effects and associated laboratory tests with follow-up.
11.Suggest strategies regarding short-term memory and planning ability: Individuals may choose to write things down, develop schedules and calendars, make lists, draw pictures, and take more time when devising plans.